Improved process for extracting oils



Unrrnn STATES PATENT CHARLES A. SEELY, OF NEW YORK, N. Y.

IMPROVED PROCESS FOR EXTRACTING. OILS, 84.0.

Specification forming part of Letters Patent No. 94,246, dated August 31, 1809.

To all whom it may concern:

Be it known that I, CHARLES A. SEELY, of the city, county, and State of New York, have invented a new and Improved Method or Process of Extracting Oils, Fats, and Resins from natural and other products containing them; and I do hereby declare that the following is a full and exact description thereof.

The nature of my invention consists in the use of a volatile hydrocarbon as a solvent of fats, oils, and resins in such a way as to greatly increase the solvent power of the said hydrocarbon. This increase of solvent efficiency I secure by inclosin g the solvent and the substance from which oil, 860., is to be extracted in a closed vessel capable of withstanding a considerable pressure, and then apply heat by means of hot water or steam till the contents of the vessel are raised to a suitable high temperature.

To enable others skilled in the art to carry on my process, Iproceed to describe it and its operation more minutely.

The hydrocarbon which I prefer to use is known commercially under the name of gasoline, and is one of the products of petroleum oil. This substance, as found in market, varies considerably in gravity and volatility, and I generally choose such as has a gravity of 80 or 90 Baum; but I also find it practicable to sometimes use a solvent which has a boiling-point as low as 200 Fahrenheit. The considerations for choice as to volatility are, mainly, the cost and the facility of separation of the solvent from the oil, 850., by vaporization also, it is evident that when the oil to be extracted is volatile the solvent should be as much more volatile as possible.

The materials containing oil, &c., to which I have applied my process successfully, and to which it is well adapted, are linseed, cottonseed, mustard-seed, castor-beans, wool, cottonwaste, 850.; also, I have used the process on the cake or pomace which is left after the imperfect ordinary expression of oil by pressure; and it is evident that the process is applicable to the extraction of oil, 850., from any material of a porous nature which contains the oil, &c., distributed through it.

The dissolving-vessel is best made of boilerplate iron, and is provided with one or more man-holes or hand-holes for the admission and discharge of its contents; also, as a matter of convenience, I prefer to admit the solvent by a special pipe and to discharge the solution of oil by another special pipe, both pipes being provided with suitable stop-cocks. The size of the dissolving-vessel, which I call an extractor, will depend upon the scale on which the process is to be carried out, and the form will be such as shall be conducive to strength and convenience. I sometimes connect two or more of such extractors together in such manner that when the material in one extractor is exhausted the partially-saturated solution from one extractor may be made to pass into the next, containing fresh material. As to the form of the extractor, I find that a plain upright cylinder having a height of two to four diameters is generally suitable.

I now pass to the main feature of my invention--viz., the heating of the contents of the extractor. Gasoline of 90 Baum boils in the open air below 100 Fahrenheit, and at a temperature of 212 under confinement its va por, as I have found by experiment, has a tension of about seventy-five pounds to the square inch. It is therefore evident that a temperature much greater than 212 would be impracticable for use in my process, and that it is desirable to limit the possible temperature within a range of safety. I secure my purpose by using, as a medium of communicating heat, water and steam. Thus I surround the extractor by a hot-water or a steam jacket, or I cause the hot water or steam to circulate in a coil of pipe arranged either inside or outside of the extractor. Sometimes I cause the extractor to be immersed in a tank of water, the water of which is heated in any convenient way, as by a jet of live steam, by circulating coils of steam or water, 850. In short, I use any of the ordinary and well-known methods of conveying or communicating heat through the medium of hot water or steam.

In case I desire to use a solvent which has comparatively a low boiling-point, I find it desirable to use a high-pressure steam-say, at sixty to one hundred and fifty pounds to the square inch; or, if I wish to use water as the heating medium, I dissolve in the water some salt, alkali, or glycerine, which has the effect to raise the boiling-point.

The ordinary course of operation of my process is as follows: I charge the extractor through the man-hole with the material from which the oil is to be extracted; I secure the man-hole plate I let on the hydrocarbon solvent, and then I apply the heat through the medium of Water or steam. The heat is continued for the space of fifteen minutes or more when the solution is Withdrawn, and the solvent is separated from the oil in a suitable still.

What I claim as my invention and desire to secure by Letters Patent, is r 1. The process of extracting oils, fats, and resins herein described.

2. The use of Volatile hydrocarbon sol"- ents, in the manner and for the purpose as described.

CHARLES A. SEELY.

Witnesses:

' PHIL. F. LARNER,

JOHN A. WIEDERSHEIM. 

